STUDY ON DYNAMICS OF PDC BIT ON MULTI-LAYERED FORMATION USING ANSYS – EXPLICIT DYNAMICS / AUTODYN

This project focuses on the performance of Polycrystalline Diamond Compact (PDC) drill bit in multi-layered formations. Research papers conclude that PDC bit in market go through difficulties in order to penetrate multi-layered formations. The performance of PDC drill bit dropped when used in multi-layered formations, especially when hard formations are present. In order to investigate the performance of PDC bit, simulations will be carried out using computer aided software, since conducting experiment is much more difficult and expensive. Therefore, the purpose of this project is to model and simulate PDC bit using ANSYS. Parametric analyses were done in order to get a better understanding regarding the performance of the bit. Throughout this project, three types of simulation were done. Firstly, the project is started by constructing a preliminary model of bit, formation and fluid. Successful simulation of preliminary model proved that Audodyn can be indeed used as a solver for this simulation. Next, the reverse engineered model of PDC bit was used for the simulation. Finally, a single cutter model was used to carry out further simulations. The results of this project were obtained by varying the rake angle of the cutter, as well as using different formations such as limestone, sandstone and dolomite. From the simulations, it can be concluded that cutter with 0° rake angle gives better penetration in hard formation, whereas cutter with 10° rake angle gives better performance in soft formation. In future, Autodyn can be used to analyze the effect of drilling fluid on PDC bit performance.